202 FXUS61 KALY 071659 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 1259 PM EDT Sun Apr 7 2019 .SYNOPSIS... High pressure will move east of New England this afternoon with a southerly flow bringing some milder air and above normal temperatures across the region. Clouds thicken and increase with rain overspreading the region tonight ahead of a warm front. The rain will diminish late in the day Monday into Monday night, but another low pressure system and a cold front will bring showers back into the region for Tuesday, as well as colder temperatures heading into the mid week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Quite a bit of thin high cloudiness has spread across our region and with the light winds, even the strong April sun is not able to get temperatures to rise quite as much as earlier thought. Just some minor adjustments to temperatures and sky cover through this afternoon. Highs in the 60s but some 50s northern areas. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... Tonight...A low pressure system approaches from the central and eastern Great Lakes Region. A warm front lifts north and east tonight. The low-level baroclinic zone strengthens and shifts northeast towards the region. A low-level southwesterly jet strengthens to 30-40 kts. Some gulf moisture is briefly tapped as PWAT anomalies increase to 1 to 3 STD DEVs above normal on the latest 00Z GEFS. Clouds thicken and lower from the south and west with rain moving in especially between midnight and 6 am. PoPs were kept in the categorical range shortly before sunrise. Lows will be mild and it will become breezy in the warm advection regime with lows likely due to wet bulbing with mid and upper 40s (a few 50F readings in the Hudson River Valley) across most of the region, except upper 30s to lower 40s over the northern mtns, and across the higher terrain. Overall, it will be a mild morning. Monday...A period of stratiform rain will continue in the morning, and the latest NAM/GFS continues to show some elevated instability of with Showalter indices of 0 to -2C. A slight chance of thunderstorms was added to the forecast Monday morning especially from the Mohawk Valley, Capital Region, Berkshires south and east. The air mass is a bit more stable to the north. The stratiform rain will taper to scattered showers by the afternoon. There is still the possibility of a rumble of thunder especially for the southern locations, as the latest NAM/GFS/ECMWF/CMC have the short-wave shearing out to the north and west with the sfc wave moving northeast of the eastern Great Lakes towards northern NY and the St Lawrence. A dry slot may slide into the region by the afternoon. Large differences in the NAM and GFS MOS guidance for max temps due to the placement with the warm front. For example, the NAM MOS has a high of 55F where the GFSMOS has a 67F for Albany. We leaned close to the ECMWF MOS with lower to mid 60s into the Capital Region or basically mid 60s to around 70F from the Capital Region/Mohawk Valley south and west (except some slightly cooler readings over the eastern Catskills), and 50s to lower 60s to the north and east. It will be breezy with south to southwest winds of 10 to 20 mph shifting to the west late in the day with gusts around 25-35 mph, as a weak cold front to the system attempts to move towards the region late in the day. The placement of this boundary is tricky for the night time period. Monday night...The cold front may stall along or near the I-90 corridor. The synoptic forcing looks weak during this period. We kept a slight chance showers mainly north and east of the Capital District. It will be fairly mild again with only weak shallow cold advection with lows in the mid 30s to lower 40s north of Albany, and mainly lower to mid 40s from Albany south. The runoff should slow up due to the rain and snow melt. Total QPF the Sunday night to Monday event will be in the third of an inch to three quarters of an inch range with some slightly higher totals over the northernmost basins. Tue-Tue night...A fairly strong short-wave trough and secondary cold front quickly approaches from the Great Lakes Region. Height falls occur ahead of this disturbance with steepening mid level lapse rates close to 7C/km . Instability still looks scant with 250 J/kg or less on the latest GFS. A rumble of thunder is possible, if more instability is realized then a slight or low chance of thunderstorms may need to be added with perhaps some graupel or small hail. PoPs were increased to high chance or likely values across most of the region. Max temps will be in the upper 50s to mid 60s in the lower elevations and mid and upper 40s to mid 50s over the mountains. Strong cold advection occurs in the wake of the front and short-wave. Some of the rain showers will transition to snow showers over the southern Adirondacks, western Mohawk Valley and southern Greens especially with the favored upslope flow. An inch or so of snow is possible over the southern Greens. Lows fall back into the mid 20s to mid 30s across most of the region with a few upper 30s over the mid Hudson Valley. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... The long term period starts out dry with near normal temperatures as high pressure builds in at the surface. Northwest flow will dominate on Wednesday, leading to temperatures in the low 40s to low 50s. Overnight lows will also be a bit chilly, in the low 20s to low 30s Wednesday night. Thursday should also remain mostly dry as high pressure shifts off the east coast and as southerly flow sets up at the surface. This will result in warmer, moist air getting pulled into the region ahead of a strong low pressure system progged to lift across the Great Lakes on Friday. So on Thursday, we can expect an increase in clouds with near normal temperatures once again. There is an outside chance for a few showers Thursday afternoon as a warm front lifts northward across the forecast area. The low pressure system will cross over the Great Lakes during the day Friday, spreading rain and a surface cold frontal boundary across the region Friday afternoon into Friday night. There will be plenty of moisture available for at least some moderate rainfall during this time frame. The front and associated rainfall should exit by daybreak on Saturday, with the exception of some lake- enhanced showers across the Dacks. Temperatures Friday and Saturday will average a few degrees above normal, with highs in the upper 50s, and 40s in the Dacks. Friday night, temperatures will remain fairly mild with plenty of shower activity around, in the mid 30s to upper 40s. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... VFR conditions are expected through the day today with a surface high pressure situated over the region. Skies will remain partly cloudy today as additional mid to high level clouds increase. A low pressure system will approach the region late this evening, spreading rain across the TAF sites after 00Z/Mon. Expect flying conditions to deteriorate to at least MVFR by the end of the TAF forecast period. Light and variable winds will transition towards southerly through the forecast period at less than 10 kts. Outlook... Monday Night: No Operational Impact. NO SIG WX. Tuesday: High Operational Impact. Likely SHRA. Tuesday Night: Moderate Operational Impact. Chance of SHRA. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: No Operational Impact. NO SIG WX. Thursday Night: No Operational Impact. NO SIG WX. Friday: Moderate Operational Impact. Chance of RA. && .FIRE WEATHER... High pressure will move east of New England this afternoon with a southerly flow bringing some milder air and above normal temperatures across the region. Rain overspreads the region late tonight ahead of a warm front. The rain will diminish late in the day Monday into Monday night, but another low pressure system and a cold front will bring showers back into the region for Tuesday. Minimum RH values this afternoon will be in the 40 to 55 percent range. The RH values will recover the 80 to 100 percent tonight, and only lower to 55 to 75 percent Monday afternoon in the wet and more humid air mass. The winds will be from the south at 5 to 15 mph this afternoon and then shift to the east to southeast at 5 to 15 mph tonight. South winds 10 to 15 mph Monday will shift to west by the afternoon and at around 10 to 20 mph with gusts to 25 to 35 mph. The next widespread rainfall will be tonight into Monday. && .HYDROLOGY... No widespread hydrological problems are expected the next several days into the middle of next week. Some elevated flows due to snow melt across the southern Adirondacks and Upper Hudson Region are possible Monday into Tuesday. The next widespread rainfall with a third to three quarters of an inch across the HSA with some locally higher amounts over the southern Adirondacks will be tonight through Monday. A cold front and an upper level disturbance may bring more showers for Tuesday into Tuesday night with QPF amounts of a tenth to a half an inch. Drier weather will return for the mid week before the next system arrives late in the day Thursday into Friday. Some within bank rises are possible on rivers with the rainfall and some snowmelt from the snowpack in the southern Adirondacks and southern Greens during the week. Some of the MMEFS guidance indicates a couple inches of snow melt with the rain may cause very minor flooding at Hope and Riverbank. The latest NERFC guidance shows within bankfull rises at Hope, Hadley and Riverbank to the Alert or Caution stages. Our confidence is not great for minor flooding at this time due to limited QPF and colder air returning on Tuesday. For details on specific area rivers and lakes, including observed and forecast river stages and lake elevations, please visit the Advanced Hydrologic Prediction Service /AHPS/ graphs on our website. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...Wasula NEAR TERM...NAS SHORT TERM...Wasula LONG TERM...JLV AVIATION...JPV FIRE WEATHER...Wasula HYDROLOGY...NAS/Wasula